With the advent of the energy saving era, possible effort is directed recently particularly to research and development for effective use of solar energy. For the most effective use of solar energy, it is a must to directly use the solar energy as the light energy, namely to use the solar energy without converting it to another form of energy such as heat energy and electrical energy. From this point of view, the applicant of the present invention has proposed various kinds of solar collecting apparatuses where the solar energy is converged using lenses etc. and then guided into a photo-conductor, thereafter transmitted through said photo-conductor to the place requiring the lighting and thereby such solar energy is used for indoor lighting etc. The present invention is also proposed as a part of such apparatuses and particularly an apparatus where a means for converting the solar energy to heat energy is effectively employed into the aforementioned sunlight collecting apparatus, and thereby both light energy and heat energy of the sun can be used simultaneously only with a single apparatus.